sg->length may or may not contain the length of the dma region to transfer,
depending on the architecture - dma_sg_len(sg) always will though. For the
architectures which use the drivers modified by this patch it probably is the
case that sg->length contains the dma transfer length. But to be consistent and
future proof change them to use dma_sg_len.
To quote Russel King:
sg->length is meaningless to something performing DMA.
In cases where sg_dma_len(sg) and sg->length are the same storage, then
there's no problem. But scatterlists _can_ (and one some architectures) do
split them - especially when you have an IOMMU which can allow you to
combine a scatterlist into fewer entries.
So, anything using sg->length for the size of a scatterlist's DMA transfer
_after_ a call to dma_map_sg() is almost certainly buggy.
The patch has been generated using the following coccinelle patch:
<smpl>
@@
struct scatterlist *sg;
expression X;
@@
-sg[X].length
+sg_dma_len(&sg[X])
@@
struct scatterlist *sg;
@@
-sg->length
+sg_dma_len(sg)
</smpl>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
dmaengine drivers should always use sg_dma_address instead of sg_phys to get the
addresses for the transfer from a sg element.
To quote Russel King:
sg_phys(sg) of course has nothing to do with DMA addresses. It's the
physical address _to the CPU_ of the memory associated with the scatterlist
entry. That may, or may not have the same value for the DMA engine,
particularly if IOMMUs are involved.
And if these drivers are used on ARM, they must be fixed, sooner rather
than later. There's patches in the works which will mean we will end up
with IOMMU support in the DMA mapping later, which means everything I've
said above will become reality.
The patch has been generated using the following coccinelle patch:
<smpl>
@@
struct scatterlist *sg;
@@
-sg_phys(sg)
+sg_dma_address(sg)
</smpl>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
The Nomadik PL080 variant has some extra protection bits that
may be set, so we need to check these bits to see if the
channels are actually available for the DMAengine to use.
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Alim Akhtar <alim.akhtar@gmail.com>
Cc: Alessandro Rubini <rubini@gnudd.com>
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
When a client calls pl08x_control with DMA_TERMINATE_ALL, it is correct
to terminate and release the phy channel currently in use (if one is in use),
but the phychan_hold counter must also be reset (otherwise it could get
trapped in an unbalanced state).
Signed-off-by: Davide Ciminaghi <ciminaghi@gnudd.com>
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
For some reason I can't figure out we're reading the PL080_INT_STATUS
register instead of PL080_TC_STATUS when checking for the terminal
count. The PL080_INT_STATUS is a logical OR between the error and
terminal count status register and may not report what we want it
to, especially if there is an error and a terminal count at the same
time and the former is not lowered in time for the check in the TC
register. Make sure we read what we're actually interested in.
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Viresh Kumar <viresh.kumar@st.com>
Cc: Alim Akhtar <alim.akhtar@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Add context parameter to device_prep_slave_sg() and device_prep_dma_cyclic()
interfaces to allow passing client/target specific information associated
with the data transfer.
Modify all affected DMA engine drivers.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Provide a common function to initialize a channels cookie values.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Now that we have the completed cookie in the dma_chan structure, we
can consolidate the tx_status functions by providing a function to set
the txstate structure and returning the DMA status. We also provide
a separate helper to set the residue for cookies which are still in
progress.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Provide a common function to do the cookie mechanics for completing
a DMA descriptor.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Everyone deals with assigning DMA cookies in the same way (it's part of
the API so they should be), so lets consolidate the common code into a
helper function to avoid this duplication.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Add a local private header file to contain definitions and declarations
which should only be used by DMA engine drivers.
We also fix linux/dmaengine.h to use LINUX_DMAENGINE_H to guard against
multiple inclusion.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Every DMA engine implementation declares a last completed dma cookie
in their private dma channel structures. This is pointless, and
forces driver specific code. Move this out into the common dma_chan
structure.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
[imx-sdma.c & mxs-dma.c]
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Flow controller information is passed now from DMA_SLAVE_CONFIG option. This
patch makes changes in pl08x driver to use device_fc from it instead of platform
data.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Rewrite a duplicated test to test the correct value
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression E;
@@
(
* E
|| ... || E
|
* E
&& ... && E
)
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Currently, if plchan->phychan is true, we return immediately from
prep_phy_chan(). We must configure txd->ccfg and increment phychan_hold before
returning. Otherwise, request line number wouldn't be configured in this txd.
Reported-by: Rajeev Kumar <rajeev-dlh.kumar@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
In pl08x_free_txd(), check if pool is allocated successfully before freeing it.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Untill now, sg_len greater than one is not supported. This patch adds support to
do that.
Note: Still, if peripheral is flow controller, sg_len can't be greater that one.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Before converting the dma channel to our private data structure, first
check that the channel is indeed one which our driver registered. We
do this by ensuring that the underlying device is bound to our driver.
This avoids potential oopses if we try to reference 'plchan->name'
against a foreign drivers dma channel.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
At least, on SPEAr platforms there is one peripheral, JPEG, which can be flow
controller for DMA transfer. Currently DMA controller driver didn't support
peripheral flow controller configurations.
This patch adds device_fc field in struct pl08x_channel_data, which will be used
only for slave transfers and is not used in case of mem2mem transfers.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
When we have DMA transfers between peripheral and memory, then we shouldn't
reduce width of peripheral at all, as that may be a strict requirement. But we
can always reduce width of memory access, with some compromise in performance.
Thus, we must select peripheral as master and not memory.
Also this rearranges code to make it shorter.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Currently lli_len is aligned to min of two widths, which looks to be incorrect.
Instead it should be aligned to max of both widths.
Lets say, total_size = 441 bytes
MIN: lets check if min() suits or not:
CASE 1: srcwidth = 1, dstwidth = 4
min(src, dst) = 1
i.e. We program transfer size in control reg to 441.
Now, till 440 bytes everything is fine, but on the last byte DMAC can't transfer
1 byte to dst, as its width is 4.
CASE 2: srcwidth = 4, dstwidth = 1
min(src, dst) = 1
i.e. we program transfer size in control reg to 110 (data transferred = 110 * srcwidth).
So, here too 1 byte is left, but on the source side.
MAX: Lets check if max() suits or not:
CASE 3: srcwidth = 1, dstwidth = 4
max(src, dst) = 4
Aligned size is 440
i.e. We program transfer size in control reg to 440.
Now, all 440 bytes will be transferred without any issues.
CASE 4: srcwidth = 4, dstwidth = 1
max(src, dst) = 4
Aligned size is 440
i.e. We program transfer size in control reg to 110 (data transferred = 110 * srcwidth).
Now, also all 440 bytes will be transferred without any issues.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Code for creating single byte llis is present at several places. Create a
routine to avoid code redundancy.
Also, we don't need one lli per single byte transfer, we can have single lli to
do all single byte transfer.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
max_bytes_per_lli = bd.srcbus.buswidth * PL080_CONTROL_TRANSFER_SIZE_MASK;
This is confirmed by ARM support guys.
Below is summary of mail exchange with them:
[Viresh] What is the total data to be transferred in case source and destination
bus widths are different. Suppose, source bus width is 2 bytes and destination
is 4 bytes. Now in order to transfer 80 bytes, what should be value of
TransferSize field in control reg: 40? or 20?.
[David from ARM] The value that is programmed into the TransferSize field should
be the number of <SourceWidth> transfers needed to achieve the required data
transfer.
So, to transfer 80 bytes, with a Source Width of 2, the TransferSize field =
should be programmed with:
Total transfer size
------------------- = 40
<source width>
[Viresh] Will this change if source is 4 bytes and dest is 2?
[David] Yes - the calculation then becomes:
Total transfer size
------------------- =20
<source width>
Also, max_bytes_per_lli must be calculated after fixing src and dest widths not
before that. So move this code to the correct place.
This patch also removes max_bytes_per_lli from earlier print message, as till
that point max_bytes_per_lli is unknown.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Pl080 Manual says: "Bursts do not cross the 1KB address boundary"
We can program the controller to cross 1 KB boundary on a burst and controller
can take care of this boundary condition by itself.
Following is the discussion with ARM Technical Support Guys (David):
[Viresh] Manual says: "Bursts do not cross the 1KB address boundary"
What does that actually mean? As, Maximum size transferable with a single LLI is
4095 * 4 =16380 ~ 16KB. So, if we don't have src/dest address aligned to burst
size, we can't use this big of an LLI.
[David] There is a difference between bursts describing the total data
transferred by the DMA controller and AHB bursts. Bursts described by the
programmable parameters in the PL080 have no direct connection with the bursts
that are seen on the AHB bus.
The statement that "Bursts do not cross the 1KB address boundary" in the TRM is
referring to AHB bursts, where this limitation is a requirement of the AHB spec.
You can still issue bursts within the PL080 that are in excess of 1KB. The
PL080 will make sure that its bursts are broken down into legal AHB bursts which
will be formatted to ensure that no AHB burst crosses a 1KB boundary.
Based on above discussion, this patch removes all code related to 1 KB boundary
as we are not required to handle this in driver.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Currently, if error interrupt occurs, nothing is done in interrupt handler (just
clearing the interrupts). We must somehow indicate this to the user that DMA is
over, due to ERR interrupt or TC interrupt.
So, this patch just schedules existing tasklet, with a print showing error
interrupt has occurred on which channels.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
We have just executed following in pl08x_get_phy_channel():
ch->signal = -1;
We don't have to compare "ch->signal < 0", as this will always be true.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Simply writing 1 on bit 0 is sufficient instead of reading and clearing bits.
Also as per manual, for bit 3-31 of DMACConfiguration register:
"read undefined, write as 0"
So, we must not rely on values read from this registers bit 3-31.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Insert notifiers for the runtime PM API. With this the runtime PM layer kicks in
to action where used.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
For 8 memory and 16 slave channels 35 boot print lines are printed. And that is
too much. Most of this would be more useful for debugging. So moving few of them
to dev_dbg instead of dev_info. Now only 3 prints will be printed.
This also rearrange one of the debug message to fit into two lines.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Similar comment is present over routine also pl08x_choose_master_bus(). Keeping
one of them. Also rewrite that comment to convey message clearly.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
As mentioned in Documentation/CodingStyle,
The preferred form for passing a size of a struct is the following:
p = kmalloc(sizeof(*p), ...);
The alternative form where struct name is spelled out hurts readability and
introduces an opportunity for a bug when the pointer variable type is changed
but the corresponding sizeof that is passed to a memory allocator is not.
This patch replaces (struct xyz) with *ptr at several occurrences in driver.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Header files included in driver are not present in alphabetical order. Rearrange
them in alphabetical order.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
There were few formatting related issues in code. This patch fixes them.
Fixes include:
- Remove extra blank lines
- align code to 80 cols
- combine several lines to one line
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Something changed during the 3.1 merge window in the include files
which now causes the pl08x DMA engine driver to fail to build. Fix
this by adding the now necessary dma-mapping.h include:
drivers/dma/amba-pl08x.c: In function ■pl08x_unmap_buffers■:
drivers/dma/amba-pl08x.c:1524: error: implicit declaration of function ■dma_unmap_single■
drivers/dma/amba-pl08x.c:1527: error: implicit declaration of function ■dma_unmap_page■
Acked-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
pl08x_width function does not handle rest of enums for DMA_SLAVE_BUSWIDTH_xxxx
which causes gcc to emit below warining
drivers/dma/amba-pl08x.c: In function 'pl08x_width':
drivers/dma/amba-pl08x.c:1119: warning: enumeration value
'DMA_SLAVE_BUSWIDTH_UNDEFINED' not handled in switch
drivers/dma/amba-pl08x.c:1119: warning: enumeration value
'DMA_SLAVE_BUSWIDTH_8_BYTES' not handled in switch
this patch adds a default case which returns error
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Now that we have separate cctl values for M>P and P>M transfers, we can
avoid calculating the cctl value each time we prepare a transaction.
Move the bus selection and increment setting to the slave configuration
and initialization functions.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Store the source/destination cctl values into the channel structure.
This moves us towards being able to avoid a configuration call each
time we use the channel.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Store the source/destination slave address separately into the channel
structure. This moves us towards being able to avoid a configuration
call each time we use the channel.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Clean up debugging when setting up the LLI list. This reduces the
amount of output while preserving the information, and makes it easier
to read.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Avoid re-selecting the LLI bus each time we create an LLI. Move it out
of the LLI setup loops.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
PL08X_WQ_PERIODMIN and PL08X_MAX_ALLOCS are not used, remove them.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Make Primecell driver probe functions take a const pointer to their
ID tables. Drivers should never modify their ID tables in their
probe handler.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Lars-Peter Clausen
Vinod Koul
Linus Walleij
Davide Ciminaghi
Alexandre Bounine
Russell King - ARM Linux
Viresh Kumar
Julia Lawall
Linus Torvalds
Dave Martin
Russell King
Vinod Koul